Wednesday, October 13, 2010

Travels with Nightsnake

California nightsnake.  Ranger E has a calm way with snakes.  She's observed that individual snakes often have uniquely shaped spots.  With careful photodocumentation of their spots, I may be able to tell the difference between future nightsnakes.
This is the third fall season I have found a nightsnake on the Dipper Ranch.  In October 2007, I had just moved onto the ranch and didn't know what a nightsnake was. Fortunately, something seemed odd about the small, brown-spotted snake in the springbox in those first few weeks, so we walked the dripping net back to the house to take photos.  With frequent reference to our burgeoning natural history library, I eventually learned to tell the difference between the 4 local brown-spotted snakes:  gopher snake, rattlesnake, nightsnake and juvenile yellow-bellied racer.

Nightsnakes' vertical pupils are slitlike in the sun.
Hunting at night, thus their name and apparent cat-eye adaptation to darkness.
California nightsnakes are small, have bright, coppery-gold eyes with vertical pupil slits, and are covered by brown rectangles down their tan length to their sharply pointed tail.  A unique feature about them are the distinctly-shaped marks on their necks.  Stebbins and California Herps describe these as dark brown blotches, usually arranged in a pair, and sometimes connected.  The Dipper Ranch nightsnakes have a three-part neck mark in the shape of a elaborate cross or a speared "M" (when looking from the head of the snake). Nightsnakes also have a dark bar behind or through the lower eye that contrasts with the whitish scales of the upper lip.

2007 California nightsnake
Nightsnakes are mildly venomous, just enough to subdue small prey when punctured with specialized teeth at the back of their jaw.  They generally live in arid but well-vegetated areas such as chaparral, scrub, deserts and grasslands.  Active at night and the crepuscular hours, they hunt mostly lizards and their eggs, but also small snakes and other reptiles, amphibians, and invertebrates.

2008 California nightsnake with dorsal spots looking like crooked figure 8's.
In September 2008, I checked the springbox right before going to a neighborhood party and found another nightsnake.  I tucked this one into a portable terrarium and took him to the party.  I figured nightsnakes were probably strangers to most of my neighbors, so showing them its unthreatening face might prevent fellow nightsnakes from being misidentified and unfortunately killed as rattlesnakes.  I made sure to check with the hostess before unveiling the snake in her house.  She is a wildlife enthusiast, a character out of a Santa Cruz Mountains version of All Things Wild and Wonderful.  Midparty, I invited people into the kitchen for a nightsnake viewing so that any guests of ophiophobia tendency could stay in the living room.  Within a few minutes, all the party guests were crowded into the kitchen - that's my adventurous country neighbors.

The nightsnake was a hit and handled his fame quite calmly.  Later that night, we returned to the Dipper Ranch and I released the party animal on a slope behind the barn.

California nightsnake on linen.
My attempt to photodocument 2010 nightsnake before release.
Recently, on August 31, I found another nightsnake which measured approximately 14" SV (snout to vent), 16" TL (total length).   I think this was a female as her tail length was short past the vent.  Male snakes tend to have longer and broader tails because that is where they store their reproductive parts.  As you can see, every time I meet a nightsnake, I'm learning more about them.

I can't tell if I've been catching the same or different nightsnakes each year since I haven't been marking them as I have been marking rattlesnakes.  It's hard to compare the snakes by prior years' photographs since I'm using a new camera and my photography has improved since 2007.

Check out the rapidly vibrating tongue on this nightsnake.
The Midpeninsula Regional Open Space District was having a staff recognition event at Mindego Ranch the next day, so I decided it would be a great opportunity for staff to become familiar with the distinct pattern of this unusual, local resident.  Nightsnake #3 went into the portable terrarium.  The next day, I walked cross-country to Mindego Ranch (as part of my previously described Vulture Quest), and this gal went along in my backpack.

The female San Francisco gartersnake is a handful.
Throughout the day, my co-workers and I went on bird walks to Big Springs and on hikes to the top of Mindego Hill.  To help us learn about the rare animals that live at Mindego Lake on this recently acquired property, biologist J had invited the San Francisco Zoological Society staff to make a presentation.  They showed us a southern Pacific pond turtle (Actinemys marmorata pallida) and a male and a female San Francisco gartersnake (Thamnophis sirtalis tetrataenia) and described their behavior and habitat.

We know San Francisco gartersnakes live at Mindego Lake, and occasionally a ranger or biologist get a quick view of one whipping through the grasslands, glide-hunting in the shallow margins of the lake, hanging in a willow tree, or basking on the dirt roads.  We'll be putting up "Slow - Snake Crossing" signs.

It's hard to get people excited about snakes, and even harder to get them interested in protecting snakes which are rarely seen.  The San Francisco Zoo is working with the US Fish and Wildlife Service on a snake education program.  Zoo staff take live San Francisco gartersnakes to schools and community meetings in the snake's limited historic range (basically the San Francisco peninsula) to help people appreciate this colorful original resident.  Also, zoo staff provide treatment for any injured wild San Francisco gartersnakes, or those which need to be temporarily moved during recovery actions like the restoration of wetlands, and may become involved in a captive breeding program. Whereas the Open Space District purchases and preserves natural land, the zoo's programs may help reintroduce San Francisco gartersnakes to former habitat in the wild.

An inspiring moment on the job: up-close and personal learning about a rare snake.
Something a ranger is sure to share with preserve visitors.
As Jessie Bushnell brought each snake out and described them, all types of Open Space staff (rangers, accountants, equipment operators, Board members, etc.) listened attentively, asked questions, and crowded around to get a better view of the San Francisco gartersnake which Robert C. Stebbins refers to as "One of the most beautiful serpents in N. America."  Buying property, cleaning up dumps to restore land to natural conditions, planning ecologically sensitive trails, getting permits, hiring contractors, and so forth can be difficult and stressful work.  It is wonderful to experience these wild ambassadors up close now and then to remind us why we are doing this job.

As the hubbub from the San Francisco gartersnake calmed down, I pulled out Nightsnake #3 to compare it to a gopher snake the zoo staff also brought.  Although not as colorful or rare as the San Francisco gartersnake, this small brown-blotched and rarely seen snake emphasizes the more subtle biodiversity in the Santa Cruz Mountains.

California nightsnake on left - notice double row of rectangular blocks in an offset checker pattern on back.
Larger gopher snake on right with single crosswise blocks on back.
Our general manager, an experienced naturalist, joined me in describing the nightsnake. Later, he subtly pulled me aside to correct a misstatement I made.  I had commented that nightsnakes are one of the lyre snakes as demonstrated by the distinct blotch behind their heads --- WRONG!  He quietly corrected me by clarifying that nightsnakes are not a type of lyre snake.  I believed him, however, confused I went back to my still burgeoning natural history library to see how I picked up this error.  Not a single one of my books or bookmarked websites said anything about nightsnakes being a lyre snake.  However, in every single case, the nightsnakes were included in a section directly after the lyre snakes.

Lyre snakes are also slightly venomous, cat-pupiled, brown-blotched snakes with a distinct mark on their neck.  However, their neck tattoo is "V"-shaped (when the snake is viewed from the tail).  I must have made a leap-of-faith 'spot' association between the two marked snakes.  Mea Culpa.  I'm grateful to be working with people who get excited about snakes and who also help us get our facts straight.  I am constantly seeing and learning new things at the Dipper Ranch.  If you see anything wrong on the Dipper Ranch blog, please let me know.  I intend to keep learning and sharing fascinating snake faces and fates.

Be careful grabbing for that tool in the field.
See also:

Robert  C. Stebbins, Western Reptiles and Amphibians, Third Edition, 2003.

7 comments:

  1. My apologies to readers getting multiple RSS feeds on the same post. I am still getting used to new features on Blogger.

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  2. Love your snake posts, as not many people blog about them. I've learned so much from you. I appreciate that you are okay correcting yourself. We're always learning. Thank you.

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  3. Sometimes I can't believe this botanist is writing about snakes, vultures and frogs, but what's a gal to do when it is so interesting? The culture of blogging provides the opportunity of timely writing without expectations of 100% accuracy since the readers will usually catch any mistakes within a short period of time. Hooray!

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  4. Beautiful snakes! It's wonderful that you're using them to educate people. Maybe you'll help get a few more poeple past the "AAAUUUGH!! KILL IT!!" instinct, and experience the "Wow, that's gorgeous!" moment.

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  5. The nightsnake is a new one for me. Thanks for all the details on this lovely creature. And kudos to you for sharing your enthusiasm for snakes with others.

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  6. That's awesome. When we first (only time?!?) saw one at work (in So. Cal., when ranger) there happened to be a major herpetologist in the park meeting with me, so we drove him over and he said "night snake." I'd never HEARD of it. He said the brown kidney shaped blotches on the neck are the key.

    Lovely little creatures. I'm going to have to look up juvenile yellow-bellies racer, 'cause THAT one I don't know! Nice picture. Thanks for sharing!

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  7. Hi Cindy, I really enjoy your reflections on nature and eagerness to learn. I'm the same way. You've got some great snakes there, I sure like the pictures.

    Looking forward to what fall will bring at Dipper Ranch!

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